County profile · official public datasets

Union County, TN

61 public highway bridges tracked in the FHWA National Bridge Inventory: 37.7% rated Good, 57.4% Fair, 4.9% Poor.

61
Public bridges: 37.7%
Good condition: 4.9%
Poor condition

The verdict

According to the Federal Highway Administration's 2024 National Bridge Inventory.

Union County posts a higher-than-median Poor-condition share among rated counties in the state across rated county bridge inventory.

67th
of 95 on Poor share: 4.9%
Poor-condition share: 61
public highway bridges: 1979
avg year built

Poor is an FHWA condition category from the lowest applicable component rating (4 or below), not a live crossing-safety or closure decision. Rankings cover counties with at least five public highway bridges.

Union County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Union County ranks #67 of 95 Tennessee counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 4.9%). Union County, Tennessee contains 61 public highway bridges. Roughly 37.7% are rated “Good,” 57.4% “Fair,” and 4.9% “Poor.” Poor means the lowest applicable deck, superstructure, substructure, or culvert rating is 4 or below on the 0–9 NBI scale. It is a condition category, not a live safety or closure decision.

Responsible agencies inspect covered bridges on risk-based intervals under current NBIS rules and submit inventory data to FHWA annually. The list below shows every NBI-tracked bridge in the county. Use the “Sort by” controls to change the ordering, and click any row for its reported inspection date, traffic count, and condition fields.

Source: FHWA National Bridge Inventory. See methodology for full definitions.

Total bridges

Public highway bridges in Union County

Good condition

37.7%

23 of 61 rated 7-9

Fair condition

57.4%

35 of 61 rated 5-6

Poor condition

4.9%

3 of 61 rated 4 or below

In-state Poor-share rank

#67 of 95

Among Tennessee counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 61 NBI-tracked bridges by lowest applicable component rating.

Good

37.7% (23)

Fair

57.4% (35)

Poor

4.9% (3)

Union County's Poor-condition bridges carry 340 vehicle crossings a day

That is 0.4% of the county's reported daily bridge traffic on 4.9% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 113 crossings a day against 963 for a Good-condition one. A Poor rating is a condition category, not a closure or a live safety judgement; it means the lowest applicable component rating is 4 or below.

Computed over the 61 of 61 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

41% of Union County's bridges have passed the 50-year mark

25 of the 61 bridges with a recorded construction year were built in 1974 or earlier. Age alone is not a defect: a well-maintained older bridge can rate Good, and 37.7% of this county's inventory does. Even so, this older cohort is the population from which future Poor ratings are drawn, which is why the age profile below matters alongside the condition split above.

Cutoff derives from the 2024 release year minus a 50-year design life. Source: FHWA National Bridge Inventory, 2024 release.

One structure carries 61.8% of the county's Poor-condition bridge traffic

NFA A156 over N FORK BULL RUN CREEK, built 1975, carries 210 vehicles a day, the most of any Poor-rated structure here. The county's Poor-condition exposure is concentrated rather than evenly spread, so the 3-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 340 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1930s

1
1940s

6
1950s

2
1960s

7
1970s

14
1980s

16
1990s

3
2000s

3
2010s

6
2020s

3

What this shows Construction peaked in the 1980s, when 16 of the county's bridges still in the inventory were built, which is 26.2% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year (1979) matches the Tennessee average (1977).

How Union County compares with Tennessee's closest counties by inventory size

The 5 Tennessee counties nearest Union County in number of bridges, with their condition splits. Its 4.9% Poor share is the 4th-lowest of these 6. Its average build year of 1979 against a peer-group mean of 1981 is in line with the group.

Showing the 5 closest of 94 Tennessee counties eligible for comparison.

Bridge inventory size and condition shares for Union County and the 5 Tennessee counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Moore County	69	53.6%	46.4%	0%	1974
Sequatchie County	67	47.8%	52.2%	0%	1980
Clay County	64	64.1%	29.7%	6.3%	1984
Hancock County	61	47.5%	50.8%	1.6%	1985
Union County (this page)	61	37.7%	57.4%	4.9%	1979
Fentress County	55	30.9%	52.7%	16.4%	1981

Each share is of that county's own total tracked bridges; peers are the counties with 5 or more bridges whose inventory size is closest to Union County's. Source: FHWA National Bridge Inventory, 2024 release.

Nationwide counties with similar inventory size or average build year

Two NBI-derived peer sets for Union County, both outside Tennessee so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside TN (61 bridges here).

Amador County, CA · 61 bridges
Cheyenne County, CO · 61 bridges
Montezuma County, CO · 61 bridges
Atkinson County, GA · 61 bridges

Similar average build year

Nearest mean year-built outside TN (1979 here).

Pima County, AZ · avg 1979 · 1,150 bridges
Jefferson County, KY · avg 1979 · 662 bridges
Spartanburg County, SC · avg 1979 · 638 bridges
McPherson County, KS · avg 1979 · 586 bridges

Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.

All 61 Good 23 Fair 35 Poor 3

Good-condition bridges (23)

Sort:

Union County Bridge Snapshot

Condition distribution

Union County's Poor-condition bridges carry 340 vehicle crossings a day

41% of Union County's bridges have passed the 50-year mark

One structure carries 61.8% of the county's Poor-condition bridge traffic

How Union County compares with Tennessee's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

Good-condition bridges (23)

NFA A316

NFA D331

NFA A122

NFA A167

NFA A173

NFA D334

NFA 1274

NFA 1345

NFA A120

NFA A120

NFA A121

NFA A121

NFA A122

NFA A137

NFA A156

NFA A156

NFA D346

NFA 1299

NFA 1090 (SA 8711)

NFA 1090 (SA 8711)

FAP 33

FAS 144

FAS 144

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